Post by Albertabuck on Sept 20, 2021 21:09:42 GMT -6
K, guess I should have threw this out there a few nites ago, but seeing how most often I'm one of the most common to answer these types of questions I hesitated...well three days of messing around I am out of ideas and have enlisted some help.
Engine is in my NH Stackcruiser, Industrial 361, engine is a 76, breaker ignition, Holley 2300 2V carb with vacuum controlled governor set at 2750RPM. Machine has total of 2700 plus hours running time. Unit runs Ford running gear, 4 spd tranny to a 17K 2 spd rear truck axle.
Engine was running perfectly during summer season and prior to me replacing the alternator just before I stacked several hundred 2nd cut hay last week. Field was right at home where stack is, so never got out of second gear. Noticed while dumping last load, engine seemed a bit rough, and would stall most times while unloading when you hit the brakes at an idle.
The twit who owned this machine before me for some reason had butchered (among other things) a Delco alternator on to it in place of the original Motorcraft. Alternator was getting weak and since it was already wired for Delco, I install a Delco school bus alternator, not sure of amps, I'm guessing be bit over 100. Its about half again the physical size of a normal automotive Delco, but not anything like the large ones you most often see on out trucks or large 4wds. Reason I wanted the big one is for high output with all the lights as most often I don't run the machine much over half throttle while picking, and then when it idles down, big time drain on battery. Was a used alternator off an old bus I have, worked good, charged like it should. Peak voltage was was 14.3, averaged 13.7.
Reason I mention the alternator, is that is what seems to have set in motion what has become a total circlejerk and me shaking my head.
After noticing it was running rough after stacking that 2nd cut, I decided to give a pit of check over and tune up, as I need to haul a couple thousand straw about 6 miles one way, so a few trips. Pulled the cap off, which BTW, this machine still had the original cap on it, is NH red from when painted, and noticed points, cap and rotor all fairly burnt. No big deal, was actually surprised it had run as good as it had. Replaced everything cap rotor condenser and points. Initially started and run good, but never put it above an idle at the time. Threw the timing light on it, was a couple degrees retarded, set it right and left everything else alone.
Then when I needed it, fire it up, everything good till I get out on the road and once I grab third gear, I instantly notice its really lacking power and it starts this loping or surging, like as if it starving for fuel, then gets a shot, then starving, this keeps repeating in almost a rhythmic pattern as long as you got your foot on the throttle, wide open or just half, same thing. Would actually spin the rear tires each time it would leap forward. First thought was fuel issue, checked everything, nope. Then thought maybe governor, nope not that either. Rechecked ignition components, nope nothing there. Then figured must be carb. Pulled it off and opened it up, everything looked good and as it should. Put it back on, same results. Figured carb buggered. Don't have a kit, no one around does, be several days to get one weekend was in play so went a different route.
Had a known good 2v Motorcraft carb off my Merc one ton in the shop, bolted it on, had to modify a few things to get everything flanged up, fired it up, wasn't perfect but it seemed to run ok. Out for a test drive, come out second into third and bingo, the loping returns.....
So now chances of two different carbs having same issue is virtually impossible, so Holley went back on, and now I dig deeper into ignition. Find of the genius before me had installed an electronic ignition coil, that kicked in the brain to realizing that most likely when the system voltage increased with the new alternator, so did coil output, would make sense it would burn the shit out of everything as it did. Engine is wired with a ballast resistor which is working as it should, when running output to coil is about 8.7 volts. Changed that out to a known good original older breaker ignition Ford coil, again no difference, but at least got the right power going to the plugs now. Checked vacuum, 16 to 20 inches. Then pulled the exhaust manifold heat shields and original plug wires and turfed whole works into a pile. Pulled and checked plugs, all looked good, engine been running well, they tell the story. Reinstalled them along with a good set of used wires, again from a breaker point system. Again, all of this was for naught, though dam it idles nice. Then started adjusting the timing manually. Seemed if I retared it several degrees, it would pull better, but still loped and then of course run hot. Oh and somewhere along the way, I also installed a large electric fuel pump between the tank and original Ford mechanical one just in case it was losing capacity at high speed. Needless to say all filters, carb fuel inlet screen and such have been looked at. Is not the tank vent either.
Also did more than one road test with vacuum governor disconnected, no difference, except under no load, it will rev right up there as one would expect.
One thing I never mentioned yet, is when parked and the Holley hooked up complete, crack the throttle to the governor and it climbs to 2780, so governor is dead on and working proper, however once it reaches peak RPM, it begins surging between 2780 down to @2300, again in a rhythmic pattern, not a fast one either, its like one was slowly rocking the throttle linkage back and forth. But engine runs very smooth, no stutter, or hesitation. From an idle can start out in second gear with just a bit of throttle, same as I always did before.
Have also dug into the advance system of distributor, its the dual system, vacuum and mechanical, both seem to be working as they should. I even did a road test with the vacuum advance plugged off and disconnected, again no difference.
So with all of this and three days of my time into this, I reached out to the only person I know that has more experience with these old systems than I do, when I called and asked, he was like holy shit, you must be baffled if you need help, your place or mine? He's actually nest door to where my straw is at so I managed to get it to his yard this afternoon. We're gonna look into it tomorrow together.
So if anyone gots any ideas, lets hear them. I have never run across an issue like this before. I'm hoping I am over looking something obvious, too many irons in the fire, getting stressed over this and the time I've lost, so maybe the brain aint working as good as it should be. Trouble is, everything Bob asked about, I had already been there...so now he's scratching his head and he ain't even heard it run yet as he wasn't home when I dropped it off
I'm going to bed, think stress getting to me. I'll check in the morning before I head over to the neighbors.
Thanks.
Engine is in my NH Stackcruiser, Industrial 361, engine is a 76, breaker ignition, Holley 2300 2V carb with vacuum controlled governor set at 2750RPM. Machine has total of 2700 plus hours running time. Unit runs Ford running gear, 4 spd tranny to a 17K 2 spd rear truck axle.
Engine was running perfectly during summer season and prior to me replacing the alternator just before I stacked several hundred 2nd cut hay last week. Field was right at home where stack is, so never got out of second gear. Noticed while dumping last load, engine seemed a bit rough, and would stall most times while unloading when you hit the brakes at an idle.
The twit who owned this machine before me for some reason had butchered (among other things) a Delco alternator on to it in place of the original Motorcraft. Alternator was getting weak and since it was already wired for Delco, I install a Delco school bus alternator, not sure of amps, I'm guessing be bit over 100. Its about half again the physical size of a normal automotive Delco, but not anything like the large ones you most often see on out trucks or large 4wds. Reason I wanted the big one is for high output with all the lights as most often I don't run the machine much over half throttle while picking, and then when it idles down, big time drain on battery. Was a used alternator off an old bus I have, worked good, charged like it should. Peak voltage was was 14.3, averaged 13.7.
Reason I mention the alternator, is that is what seems to have set in motion what has become a total circlejerk and me shaking my head.
After noticing it was running rough after stacking that 2nd cut, I decided to give a pit of check over and tune up, as I need to haul a couple thousand straw about 6 miles one way, so a few trips. Pulled the cap off, which BTW, this machine still had the original cap on it, is NH red from when painted, and noticed points, cap and rotor all fairly burnt. No big deal, was actually surprised it had run as good as it had. Replaced everything cap rotor condenser and points. Initially started and run good, but never put it above an idle at the time. Threw the timing light on it, was a couple degrees retarded, set it right and left everything else alone.
Then when I needed it, fire it up, everything good till I get out on the road and once I grab third gear, I instantly notice its really lacking power and it starts this loping or surging, like as if it starving for fuel, then gets a shot, then starving, this keeps repeating in almost a rhythmic pattern as long as you got your foot on the throttle, wide open or just half, same thing. Would actually spin the rear tires each time it would leap forward. First thought was fuel issue, checked everything, nope. Then thought maybe governor, nope not that either. Rechecked ignition components, nope nothing there. Then figured must be carb. Pulled it off and opened it up, everything looked good and as it should. Put it back on, same results. Figured carb buggered. Don't have a kit, no one around does, be several days to get one weekend was in play so went a different route.
Had a known good 2v Motorcraft carb off my Merc one ton in the shop, bolted it on, had to modify a few things to get everything flanged up, fired it up, wasn't perfect but it seemed to run ok. Out for a test drive, come out second into third and bingo, the loping returns.....
So now chances of two different carbs having same issue is virtually impossible, so Holley went back on, and now I dig deeper into ignition. Find of the genius before me had installed an electronic ignition coil, that kicked in the brain to realizing that most likely when the system voltage increased with the new alternator, so did coil output, would make sense it would burn the shit out of everything as it did. Engine is wired with a ballast resistor which is working as it should, when running output to coil is about 8.7 volts. Changed that out to a known good original older breaker ignition Ford coil, again no difference, but at least got the right power going to the plugs now. Checked vacuum, 16 to 20 inches. Then pulled the exhaust manifold heat shields and original plug wires and turfed whole works into a pile. Pulled and checked plugs, all looked good, engine been running well, they tell the story. Reinstalled them along with a good set of used wires, again from a breaker point system. Again, all of this was for naught, though dam it idles nice. Then started adjusting the timing manually. Seemed if I retared it several degrees, it would pull better, but still loped and then of course run hot. Oh and somewhere along the way, I also installed a large electric fuel pump between the tank and original Ford mechanical one just in case it was losing capacity at high speed. Needless to say all filters, carb fuel inlet screen and such have been looked at. Is not the tank vent either.
Also did more than one road test with vacuum governor disconnected, no difference, except under no load, it will rev right up there as one would expect.
One thing I never mentioned yet, is when parked and the Holley hooked up complete, crack the throttle to the governor and it climbs to 2780, so governor is dead on and working proper, however once it reaches peak RPM, it begins surging between 2780 down to @2300, again in a rhythmic pattern, not a fast one either, its like one was slowly rocking the throttle linkage back and forth. But engine runs very smooth, no stutter, or hesitation. From an idle can start out in second gear with just a bit of throttle, same as I always did before.
Have also dug into the advance system of distributor, its the dual system, vacuum and mechanical, both seem to be working as they should. I even did a road test with the vacuum advance plugged off and disconnected, again no difference.
So with all of this and three days of my time into this, I reached out to the only person I know that has more experience with these old systems than I do, when I called and asked, he was like holy shit, you must be baffled if you need help, your place or mine? He's actually nest door to where my straw is at so I managed to get it to his yard this afternoon. We're gonna look into it tomorrow together.
So if anyone gots any ideas, lets hear them. I have never run across an issue like this before. I'm hoping I am over looking something obvious, too many irons in the fire, getting stressed over this and the time I've lost, so maybe the brain aint working as good as it should be. Trouble is, everything Bob asked about, I had already been there...so now he's scratching his head and he ain't even heard it run yet as he wasn't home when I dropped it off
I'm going to bed, think stress getting to me. I'll check in the morning before I head over to the neighbors.
Thanks.
Now it runs very well.